Rock drill



Sept. 28, 1937. E. G. GARTIN 2,094,353

A ROCK DRILL v` Filed April 29,l 19:55

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Patented Sept. 28, 1937 UNITE@ STATES ROCK DRILL Elmer G. Gartin, Claremont, N. H., assigner to Sullivan Machinery Company, a. corporation of Massachusetts Application April 29, 1935, Serial No. 18,845

11 Claims.

This invention relates to rock drills, and more particularly relatesy to improvements in automatic feeding means for a hammer rock drill of the mounted drifter type. k

An object of this invention is to provide an improved automatic rock drill feeding means. Another object is to provide an improved automatic feeding means for a hammer rock drill wherein feed is automatically effected and controlled by vibrations of the drill hammer motor during operation of the latter and having embodied the-rein improved means operable at will for effecting the reversal in the direction of feed. These and other objects will, however, hereinafter more fully appear.

In the accompanying drawing there is shown for purposes of illustration one form which the invention may assume in practice.

In the drawing,

Fig. l is a plan view of a drifter type rock drill embodying the illustrative form of the improved automatic feeding means, parts being shown in horizontal section to illustrate structural details.

Fig. 2 is a view in longitudinal section taken substantially on line 2 2 of Fig. 1, parts being shown in elevation to facilitate illustration.

Fig. 3 is a cross sectional view taken on line 3 3 of Fig. 2. l

Fig. 4 is a. cross sectional View taken on line 4-4 of Fig. 2.

Fig. 5 is a horizontal sectional View taken substantially on line 5--5 of Fig. 2.

Fig. 6 is a fragmentary sectional view taken on line @-i of Fig. 5. '35 ln this illustrative construction there is shown a hammer rock drill of the mounted drifter type comprising a guide shell l of a standard design having slidably guided thereon a hammer motor 2 of the pressure uid actuated, reciprocatory hammer piston type. The hammer motor is of an ordinary construction` comprising a cylinder 3 having a piston chamber i containing a reciprocatory hammer piston 5 for delivering impact blows to the shank of a usual drill steel 6 suitably supported within the forward end of the hammer motor cylinder. The motor cylinder 3 has lateral guides l, 'l slidably received in parallel longitudinal guideways 8, 3 formed on the opposite sides of the guide shell.

50 The improved automatic feeding means comprises a frame 9 pivotally supported on a vertical pivot pin Ill carried by a depending bracket Il preferably formed integral with the rear head block I2 of the motor cylinder 3 to swing in horir zontal'planes parallel with the plane of the shell guideways and arranged in the space therebetween in the manner shown in Fig. 1 Rotatably journaled on a vertical stud i3 carried by the swingable frame 9 is a spur gear M. As illustrated, fixed as by riveting at l5 in an edgewise 5 position to the inner vertical sides of the shell guideways 8 is a pair of racks I6 and Il respectively, and the frame 9 is swingable about its pivot to bring the gear it into meshing engagement with either of these racks. Mounted on an extension of the stud i3 is a spring pressed plunger lock I8 having a grasping portion i9 whereby the lock may be manually inserted in any one of three spaced locking openings 20 in the bracket l l thereby to lock the swingable gear frame in either of its operative positions with the gear M in meshing engagement with one or the other of the racks I6, l'l or its intermediate neutral position with the gear lil ,out of mesh with both racks. Formed integrally with the gear lil in planes above the latter is a uni-directional ratchet wheel 2i with which a spring pressed pawl 22 carried by the frame 9 is engageable for controlling the direction of rotation of the feed control gear M, the pawl slipping over the teeth of the ratchet -wheel permitting free rotation of the gear in one direction, while engaging the ratchet teeth to hold the gear against rotation in the opposite direction.

The mode of operation of the improved automatic feeding means is as follows: When it is desired to effect feed of the drill hammer motor 2 forwardly along the shell guideways 8, the operator swings the feed control gear lll into meshing engagement with the teeth on the forward 3,5 feed rack it and thereafter locks the gear in such position by inserting the plunger lock I8 in the proper lock opening 2i). Pressure fluid is then supplied in the usual manner to the hammer motor cylinder 3 to effect rapid reciprocation of the hammer piston 5 to actuate percussively the drill steel. The reciprocation of the hammer piston causes, due to the sudden reversal of movement of the hammer piston within its cylinder, vibration or recoil movement in a 1ongitudinal direction of the hammer motor as is well understood by those skilled in the art. The movement of the hammer motor in a rearward direction with respect to the shell guideways is checked automatically by the ratchet and pawl, while forward movement of the hammer motor is unimpeded since the gear M is free to rotate in a direction to permit forward feed. The action of the hammer p-iston as the latter rapidly reciprocates within its cylinder to effect percussive actuation of the drill steel causes the gear i4 to roll along the forward feed rack I6 in a direction to permit forward feed of the drill with respect to the guide shell, the pawl 22 engaging the ratchet wheel teeth to check reverse rotation of the gear While permitting free rotation of the gear in the forward feed direction. When it is desired to effect reverse feed of the hammer motor along the shell guideways, the plunger lock I8 is released and the gear frame S is swung about its pivot into its opposite position with the feed control gear I4 meshing with the teeth of the reverse feed rack l1, the gear thereafter being locked in such position by the plunger lock. When the parts are in this reverse feed position, the direction of feed is automatically reversed since the gear lll at that time rotates freely in a reverse feed direction to permit movement of the drill in a reverse direction along the shell, while the ratchet and pawl checks gear rotation in the forward feed direction. When the gear frame 9 is swung into its intermediate neutral position with the gear le out of mesh with both of the feed racks i6, Il, the feed is, of course, interrupted, it then being possible to manually slide the drill along the shell guideways in either direction as desired.

As a result of this invention, it will be noted that an improved automatic feeding means for a hammer rock drill is provided whereby feeding movement of the drill hammer motor is effected by the longitudinal vibratory or recoil movement of the hammer motor within the shell guideways. It will further be noted that by the provision of the particular double rack and swingable reverse gear construction, an improved automatic feeding means is provided which is reversible at will in an extremely simple manner, it being necessary to effect feed reversal only to swing the feed control gear from meshing engagement with one rack into meshing engagement with the other. It will further be evident that the improved automatic feeding means is of an extremely simple and rugged character which may be applied to a standard rock drill with a minimum of change. Other uses and advantages of the improved feeding means will be clearly apparent to those skilled in the art.

While I have in this application specifically described one form which the invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

l. In a rock drill, the combination with a hammer motor within which longitudinal vibrations occur during the operation thereof, of an automatic feeding means for the hammer motor controlled by the vibratory action of the latter comprising a forward feed rack, a reverse feed rack, and a feed control gear mounted on the hammer motor and movable selectively into meshing engagement with said racks.

2. In a rock drill, the combination with a hammer motor within which longitudinal vibrations occur during the operation thereof, of an automatic feeding means for the hammer motor controlled by the vibratory action of the latter comprising a forward feed rack, a reverse feed rack, a feed control gear mounted on the hammer motor and movable selectively into meshing engagement with said racks, and means operatively connected with said gear for permitting rotation thereof in only one direction regardless of which rack said gear is in mesh with.

3. In a rock drill, the combination with a hammer motor within which longitudinal vibrations occur during operation thereof, and a guide along which said hammer motor is movable, of an automatic feeding means for the hammer moto-r controlled by the vibratory action cf the latter comprising a forward feed rack, a reverse feed rack, said racks secured to said guide, a feed control gear, a frame pivotally mounted on said hammer motor to swing relative thereto and carrying said gear, said frame being swingable about its pivot to move said gear into meshing engagement with either of said racks.

fi. In a rock drill, the combination with a hammer motor within which longitudinal vibrations occur during operation thereof, and a guide on which said hammer motor is guided, of an automatic feeding means for the hammer motor controlled by the vibratory action of the latter comprising a pair of parallel racks secured in edgewise position to said guide, a gear mounted on said hammer motor for rotation about an axis at right angles to the plane of said guide and movable selectively into meshing engagement with said racks, and means operatively connected with said gear for permitting rotation of said gear in only one direction regardless of which rack said gear is in mesh with.

5. In a rock drill, the combination with a hammer motor within which longitudinal vibrations occur during the operation thereof, of an automatic feeding means for the hammer motor controlled by the vibratory action of the latter including a forward feeding element extending in the direction of feed, a spaced parallel reverse feeding element, and a feed control element mounted on said hammer motor and movable with the latter bodily longitudinally along said feeding elements during feed and movable selectively into feeding engagement with said feeding elements to effect opposite feeding movements.

6. In a rock drill, the combination with a hammer motor within which longitudinal vibrations occur during the operation thereof, of an automatic feeding means for said hammer motor controlled by the vibratory action of the latter including spaced forward and reverse toothed feeding elements arranged parallel to each other and extending parallel to the direction of feed, and a toothed feed control element movable selectively into feeding engagement with said feeding elements and movable along one or the other of the same to effect opposite feeding movements.

7. In a feeding device for a rock drill, the combination with a support and a drilling motor slidable thereon, a reciprocatory hammer piston in the motor imparting jars thereto to move the motor in two directions relative to the support, a duality of racks longitudinally of said support, a gear carried by said motor capable of operative engagement with one or the other of said racks, the jars resulting in movement of said motor tending to cause rotation of said gear inboth directions due to its operative engagement with one or the other of said racks, means for preventing the rotary motion of said gear in one direction permitting thereby the movement of said motor in a single direction during the operative engagement of said gear with one of said racks, and means for shifting said gear from one to the other of said racks, permitting thereby the movement of said motor in the other direction.

8. In a feeding device for a rock drill, the combinaton with a support and a drilling motor slidable thereon, a reciprocatory hammer piston in the motor imparting jars thereto to move the motor in two directions relative to the support, a movement resisting mechanism associated with said motor for preventing the movement thereof loin one direction, said mechanism including a duality of racks longitudinally of the support, and a gear rotatable in a single direction operatively engageable with one or the other of said racks for controlling the direction of movement l5 of said motor.

9. In a feeding device for a rock drill, the combination With a support and a drilling motor slidable thereon, a reciprocatory hammer piston in the motor imparting jars thereto to move the 20 motor in two directions relative to the support, a movement resisting mechanism associated with said motor, said mechanism including a duality of elements longitudinally of the support, a rotatable member carried by the motor, means on 25 said elements capable of interengagement with similar means of said member for causing the rotation of the latter due to the movement of said motor, stop means associated with said member for preventing the rotation thereof in 30 one direction, and operable means for causing the operative engagement of said member with one or the other of said elements to control the direction of movement of said motor.

10. In a feeding device for a rock drill, the

combination with a support and a drilling motor slidable thereon, a reciprocatory hammer piston in the motor imparting jars thereto to move the motor in two directions relative to the support, a mechanism associated with said motor for con trolling the direction of movement thereof, said mechanism including a duality of stationary toothed elements longitudinally of the support, a member carried by the motor engageable with the teeth of one or the other of said elements for controlling the direction of movement of said motor, and operable means for selectively causing the engagement of said member with the teeth of one or the other of said elements.

11. In a feeding device for a rock drill, the combination With a support and a drilling motor slidable thereon, a reciprocatory hammer piston in the motor imparting jars thereto to move the motor in two directions relative to the support, a mechanism associated with said motor for controlling the direction of movement thereof, said mechanism including a duality of toothed elementsglongitudinally of the support, a member carried by said motor for movement therewith, said member being engageable with the teeth of one of said elements for preventing the movement of said motor in one direction and with the teeth of the other of said elements for preventing the movement of said motor in the other direction, and operable means for selectively causing the engagement of said member with the teeth of one or the other of said elements.

ELMER G. GARTIN. 

